Patent GB-788813-A (GB)
Title: An improved method and means for the production of metal ingots
IPC: B22D11/126
Filed: 1955-06-24
Abstract: 788,813. Continuous-casting machines. AKTIEBOLAGET SVENSKA METALLVERKEN. June 24, 1955 [June 24, 1954; June 8, 1955], No. 18371/55. Class 83 (1). [Also in Group XXXVII] A method of casting ingots in succession comprises casting in an open-ended die and passing each ingot between positively - operated feed - rolls located beneath the die, to an ingot-holder, until the ingot reaches a platform which may be raised and lowered within the holder, means being provided which lower the platform at a predetermined rate when a pressure is exerted thereon by the ingot. The separate ingots are formed by introducing a separating layer of metal-chippings &c. into the die on the upper end of the previously cast ingot. Appartus, Fig. 1, comprises a ladle 1, mould 4, driven withdrawalrolls 6, 7 and a billet-receiver 10 which is pivotally mounted in a bearing 9 and may be swung to the position B under the control of a wire 20 passing over pulleys 21, 22 and a winding-drum 23 driven by a motor 24. The receiver 10 comprises rollers 14 and a platform 13 which is movable longitudinally of the receiver by wires 26, 27 passing over pulleys 28-35 to winding- drums 36, 37 driven by a motor 39. A rollerpath portion 15 with a hook-portion 18 may be swung about a pivot 16 by a wire 19 passing over a winding drum 78 driven by a motor 80. In operation, the descending billet abuts the platform 13 in the position shown in Fig. 1, thereby tensioning the wires 26, 27. The pulleys 34, 35 are mounted on pivoted brackets 40, 45, Fig. 2, normally urged upwardly by a predetermined air-pressure on a piston 54, acting through a hydraulic system to pistons 43, 48. Increasing pressure on the platform overcomes said predetermined pressure and the pulleys swing downwardly, closing a switch 60 to cause the motor 39 to lower the platform. The pressure on the table then decreases, the pulleys return, switch 60 opens and the motor stops, the cycle being repeated when pressure on the platform increases again. When the table has moved downwardly to such an extent that the billet has left the rolls 7, the entire weight of the billet is taken by the platform, the switch 60 is closed and the motor 39 operates until the platform reaches its bottom position, a limit-switch then stopping the motor 39 and starting motor 24 so that the receiver swings to position B. Thereat a limit-switch stops motor 24 and starts motor 39 in the reverse direction, so that the platform moves upwardly to move the billet on to the section 15. When the platform is in its top position, motor 39 is stopped and motor 80 is started, whereby the hook 18 moves below the lower end of the billet and the roller-path 15 is raised to the horizontal position where the billet may be removed, a limit-switch 84 actuated by a cam 83 stopping the motor 80. When the section 15 is in position D the motor 39 is again switched on, in the reverse direction, to lower the platform 13 to its starting position in the receiver 10, whereat a limit-switch starts motor 24 and the receiver 10 is swung up into its vertical position to receive the next billet, which has been carried downwardly by the rolls 6, 7. The motor 24 is stopped after the receiver has reached its vertical position, when the strain in the wire 20 exceeds a predetermined value, due to the movement of a bracket 62, Fig. 3, on which the pulley 22 is mounted, with consequential opening of a switch 77 in the motor-circuit. In alternative arrangements, the platform comprises a top-member, spring-urged from a bottom member. Pressure of the descending casting on the platform urges the two members together, the movement affecting potentiometers, directly or through differential - gearing, in bridge - networks, associated with an electrical system controlling the platform raising and lowering motor.